A firewall permits or denies network transmissions based upon a set of rules, and can be employed to protect against unauthorized access while permitting legitimate communications to pass. Firewall policy is normally carried out in a way such that the source Internet Protocol (IP) address in client-server mode is specified. The firewall policy is normally implemented by manually specifying the external IP address block that can be allowed access. In some instances, access may be further limited by allowable protocol.